Mount for electron discharge devices



Jan. 21, 1958 B. w. WALL MOUNT FOR ELECTRON DISCHARGE DEVICES Filed Oct.14, 1955 FIG.8.

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INVENTOR: BARBARA W. WALL,

United States Patent Patented Jan. 21, 1958 [ice MOUNT FOR ELncrRoNDISCHARGE DEVICES Barbara W. Wall, Owensboro, Ky., assignor to GeneralElectric Company, a corporation of New York Application October 14,1955, Serial No. 540,512

Claims. (Cl. 313-261) My invention relates to electron discharge devicesand more particularly to mounting structures for said electron dischargedevices.

One of the problems encountered in manufacturing electron tubes is thatof maintaining the electrode elements in proper spaced relation. Thisproblem becomes more pronounced in grid-alignment type receiving tubeswhere lateral wires of two or more grids must remain in relatively thesame position during operation when the tubes may be subjected toconsiderable vibration, shock impact, and substantial stress due toacceleration and deceleration of units in which the tubes are mounted.Such forces may result in changing the relative position of theelectrode elements with respect to each other. Any change in therelative positions of the electrodes results in a change of the tubecharacteristics, which, of course, is undesirable. Therefore, it is ofprime importance that the tube be constructed such that the electrodeelements are held in a set predetermined position.

It is, accordingly, a principal object of this invention to provide ameans and methods for imparting rigidity and mechanical strength to theelectrode assembly of electron tubes.

Another object of this invention is to expedite assembly of theelectrode elements of electron tubes.

Still another object of this invention is to provide an efficient,inexpensive, means and methods for assembling the electrode elementswithin a tube envelope.

Yet another object of this invention is to provide a means formaintaining the electronic characteristics unchanged during the life ofan electron tube.

Further objects and advantages of my invention will become apparent fromthe following description and the features of novelty which characterizemy invention will be pointed out with particularity in the claimsannexed to and forming part of this specification.

In carrying out the objects of by invention I provide a novel supportmember for securely positioning the grids in the mica spacers.

For a detailed explanation of my invention, reference is made to theaccompanying drawings in which:

Figure 1 is an elevational view, partly in cross-section, of an electrondischarge device embodying features of my invention;

Figure 2 is a cross-sectional view taken along the lines 2-2 of Figure1;

Figure 3 is an enlarged isometric view of one embodiment of theinvention;

Figures 4a, 4b, 4c are enlarged elevation views showing steps in theprocess of assembly of the embodiment of Figure 3;

Figure 5 is an enlarged isometric view of another embodiment of myinvention;

Figure 6 is an enlarged elevation view of the embodiment of Figure 5 infinal assembly;

Figure 7 is an isometric view of yet another embodiment of my invention;and

Figure 8 is an enlarged elevation view of the embodiment of Figure 7 infinal assembly.

Figure 1 shows an electron discharge device envelope 11 within which ispositioned a mount assembly 12 including an anode 13, a cathode 14, andwire wound coaxial grids 15, and 16 supported by vertical rods 17 and18, respectively, which extend through transversely disposed mica spacerplates or supports 21 and 22.

The anode 13 may be in the form of a cylinder, and engages mica spacerplates 21 and 22 at opposite ends of the cylinder. As seen in Figure 2,the mica support has spaced apertures through which the variouselectrode supports extend for the purpose of maintaining electrodes inspaced relation with respect to each other. Spacer plates 21 and 22press firmly on the glass envelope to maintain the electrodes inseparated spaced relation to the glass envelope. The connecting wires tothe various electrodes may be of conventional design and are not, perse, a part of this invention.

In accordance with one embodiment of my invention J-shaped supportmembers 23 are affixed to the portions of the grid support rods 17 and18, which extend through the apertures in mica plates 21 and 22. Theenlarged view of Figure 3 clearly shows the J-shaped support member ofmy invention. Figures 4a, 4b, and 4c are enlarged elevation views of theJ-shaped support member 23 and the portion of rod 17 extending upwardlythrough the aperture in mica support 21, and shows the process ofassembly. The J-shaped member 23 is initially placed adjacent to the rod17 so as to bear against the spacer plate 21 and leg 25 of the member 23is spot-welded, as shown in Figure 4a. The free end 24 of member 23 isnext bent against the leg 25 of member 23 to form a bight 26 (Figure4b), and spot-welded to the rod 17 at a point below the first-mentionedweld. Bight 26 is next forceably deformed to wedge against the legportion 25 of the member 23, Figure 4c, and spotwelded at a point on therod 17 near the spacer 21, thus rigidly fixing rod 17 to the mica plate21. A similar member 23 is similarly afiixed to the opposite end of rod17 and wedged against mica plate 22.

While the invention is described in detail as used in affixing gridelectrodes, it will be understood that the invention is applicable foruse in fixing any other type electrodes such as cathodes or anodeshaving portions which extend through a transverse supporting plate.

The vertical rods 17 are thus rigidly fixed to mica supports 21 and 22and inhibit any vertical movement of the grid as well as serving as ameans of grid alignment. Because the rods 17 are held rigidly there willbe no internal sag in the rods and the grid wires 15 will maintain apredetermined spaced relation with respect to each other and to theother electrodes. Once assembly of the various support members 23 iscompleted, it is assured that a proper mounted relation exists betweenthe various electrodes and also assures a rugged electrode assembly.

It will be seen that the pressing in of the bight portion 26 against therod 17 and the welding thereof to the rods results in a deformation ofthe mica 21, as shown at 19. Each deformation of the mica effects atight clamping action on the rod 17.

The U-shaped member 27 of Figure 5 is another embodiment of myinvention. The process of assembly is similar to that previouslydescribed for the J-shaped member, Figure 3, excepting that the bight 28is formed prior to welding the member to the electrode rod 17. The finalassembly is shown in Figure 6. This embodiment, it will be noted,requires but two spot welds per member instead of the three welds neededin the above-described embodiment.

The arcuate shaped member 31 of Figure 7 is still another embodimeut ofmy invention. To assemble member 3 31, the upper end portion of saidmember is welded to the rod 17, and the lower end bears on the surfaceof the plate 21. After welding, the member is straightened out to wedgeagainst the plate 21, Figure 8, to produce the deformation of the mica21 ensuring tight clamping.

Although the present invention has been illustrated by specificexamples, it will beobvious to those skilled in the art thatmodifications may be made without departing from the spirit thereof. I

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. An electron tube mount assembly comprising a planar insulatorincluding an aperture, an electrode including a support portionextending through and tightly fitted in said aperture in said insulator,a clip member having an end portion aflixed to one end of said supportportion of said electrode, said clip member extending contiguously alongthe length of said support portion to a point substantially below thenormal plane of the corresponding side of said insulator, whereby saidclip memher is effective for substantially depressing the edge of saidinsulator at said aperture out of said normal plane and into wedgingengagement with said support portion of said electrode for increasingthe tightness of said fit.

2. An electron tube mount assembly comprising a planar insulatorincluding an aperture, an electrode including a support portionextending through and tightly fitted in said aperture in said insulator,a clip member having an end portion aflixed to one end of said supportportion of said electrode, said clip member including an opposite endportion of afolded double thickness secured to said support portion ofsaid electrode and extending contiguously along the length thereof to apoint substantially below the normal plane of the corresponding side ofsaid insulator, wherebysaid opposite end portion of said clip member. iseffective for substantially depressing the edge of said insulator atsaid aperture out of said normal plane and into wedging engagement withsaid support portion of said electrode for increasing the tightness ofsaid fit. i

3. The method of mounting an electrode in an insulative spacercomprising. the steps of tightly'fitting one end of said electrode in anaperture in said spacer, securing to said end of said electrode aseparately formed elongated clip member having an arcuatefree end withsaid free end in: abutting engagementwith the corresponding surface ofsaid spacer, forcibly deforming said arcuate free end of said clipmember into straight contiguous engagement with said electrode andsecuring said free end to said electrode whereby said-free end isextended lonfree end is efiective for substantially depressing thecorresponding edge of said spacer at said aperture out of the normalplane thereof and into wedging engagement with said electrode.

4. The method of mounting an electrode in an insulative spacercomprising the steps of tightly fitting one end of said electrode in anaperture in said spacer, securing to the end of said electrode asubstantially J-shaped member having a straight portionand bight portionwith a free end, with the bight portion abutting the correspondingsurface of said spacer, bending the free end of said bight portion into'engagement with said straight portion and securing said free end to saidstraight portion and electrode, and forcibly deforming said bightportion into straight contiguous engagement with said straight portionand securing same to said straight portion and electrode'for efiectivelyelongating said member along said electrode, thereby todepress thecorresponding edge of said spacer at said aperture out. of the normalplane thereof-and-into Wedging engagement with said electrode forincreasing the tightness of the fit of said electrode in said spacer.-

5. The method ofmounting an electrode inan insulative spacercomprisingthe steps of tightlyfitting one end of-saidelectrodein an aperture insaid spacer, forniing a-clip rnember as a U-shaped' element, compressingthe strtaight portions ofsaid element together and securing sameto anend of said electrode with the bight portion of said element in abuttingengagement with the corresponding surface of said spacer, forciblydeforming said bight; portion into straight contiguous engagementbetween said straight. portions and with said electrode and securingsaidstraight' and bight portions to said elec trode'for substantiallydepressing the corresponding edge of said spacerat said aperture out ofthe normal plane and into Wedging. engagement with said electrode forincreasing the tightness of the fit of said electrode in said 1 spacer.

References Cited -in the file of thispatent UNITED STATES PATENTSlackman Mar; 30, 1937 Robertson Jan. 31, 1956

